Detection rules › Sigma
VBScript Payload Stored in Registry
Detects VBScript content stored into registry keys as seen being used by UNC2452 group
MITRE ATT&CK coverage
| Tactic | Techniques |
|---|---|
| Persistence | |
| Privilege Escalation |
Telemetry coverage
| Provider | Record / event type |
|---|---|
| Sysmon | Event ID 13: RegistryEvent (Value Set) |
Rule body
title: VBScript Payload Stored in Registry
id: 46490193-1b22-4c29-bdd6-5bf63907216f
status: test
description: Detects VBScript content stored into registry keys as seen being used by UNC2452 group
references:
- https://www.microsoft.com/security/blog/2021/03/04/goldmax-goldfinder-sibot-analyzing-nobelium-malware/
author: Florian Roth (Nextron Systems)
date: 2021-03-05
modified: 2023-08-17
tags:
- attack.privilege-escalation
- attack.persistence
- attack.t1547.001
logsource:
category: registry_set
product: windows
detection:
selection:
TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion'
Details|contains:
- 'vbscript:'
- 'jscript:'
- 'mshtml,'
- 'RunHTMLApplication'
- 'Execute('
- 'CreateObject'
- 'window.close'
filter:
TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion\Run'
filter_dotnet:
Image|endswith: '\msiexec.exe'
TargetObject|contains: '\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\'
Details|contains:
- '\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll'
- '<\Microsoft.mshtml,fileVersion='
- '_mshtml_dll_'
- '<\Microsoft.mshtml,culture='
condition: selection and not 1 of filter*
falsepositives:
- Unknown
level: high
Stages and Predicates
Stage 0: condition
selection and not 1 of filter*Stage 1: selection
selection:
TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion'
Details|contains:
- 'vbscript:'
- 'jscript:'
- 'mshtml,'
- 'RunHTMLApplication'
- 'Execute('
- 'CreateObject'
- 'window.close'
Stage 2: not filter*
filter:
TargetObject|contains: 'Software\Microsoft\Windows\CurrentVersion\Run'
filter_dotnet:
Image|endswith: '\msiexec.exe'
TargetObject|contains: '\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\'
Details|contains:
- '\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll'
- '<\Microsoft.mshtml,fileVersion='
- '_mshtml_dll_'
- '<\Microsoft.mshtml,culture='
Exclusions
The rule actively suppresses these predicates.
| Field | Kind | Excluded values | Search |
|---|---|---|---|
Details | match | <\Microsoft.mshtml,culture= | excludes:Details field:"Details" value:"<\Microsoft.mshtml,culture=" |
Details | match | <\Microsoft.mshtml,fileVersion= | excludes:Details field:"Details" value:"<\Microsoft.mshtml,fileVersion=" |
Details | match | \Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll | excludes:Details field:"Details" value:"\Microsoft.NET\Primary Interop Assemblies\Microsoft.mshtml.dll" |
Details | match | _mshtml_dll_ | excludes:Details field:"Details" value:"_mshtml_dll_" |
Image | ends_with | \msiexec.exe | excludes:Image field:"Image" value:"\msiexec.exe" |
TargetObject | match | \SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\ | excludes:TargetObject field:"TargetObject" value:"\SOFTWARE\Microsoft\Windows\CurrentVersion\Installer\UserData\" |
TargetObject | match | Software\Microsoft\Windows\CurrentVersion\Run | excludes:TargetObject field:"TargetObject" value:"Software\Microsoft\Windows\CurrentVersion\Run" |
Indicators
These rows show field, operator, and value matches.
| Field | Kind | Values | Search |
|---|---|---|---|
Details | match |
| field:"Details" kind:match |
TargetObject | match |
| field:"TargetObject" kind:match value:"Software\Microsoft\Windows\CurrentVersion" |